Part Number: UCC28780 Hello,
I am using UCC28780EVM-021. It was working properly but suddenly it is not working. I have not changed any components and the pins HVG, CS, Rtz and Rdm are not short or open circuited. I don't know the problem. I am attaching…
Part Number: UCC28780 Hello,
I am using UCC28780EVM-021. When I connect it to power supply and start increasing the voltage from 0VAC, I am observing 3 different kind of PWM pulses upto Brown-IN voltage i.e. apprx. 75VAC.
1. 0VAC to 45VAC
2. 45VAC to…
Part Number: UCC28780 Hello,
I have the 45Watt demoboard - UCC28780EVM-021, and I want understand how I can move down the start up undervoltage from 107 VDC to 95V DC or 90VDC. Can you please help me?
Wilhelm
Hi Ulrich,
Thanks for your reply.
I am looking 92% efficiency at 115Vrms and at Full load which is not average efficiency. I see 94.06% efficiency at 115Vrms and Full load in UCC28780EVM-021. I understand we have to select external component by carefully…
Part Number: UCC28780EVM-021 Other Parts Discussed in Thread: UCC28780
Above screenshot is the startup test waveform on Q2' Source and Gate in UCC28780EVM-02 . The ramp-up time is around 50ms.
We prototyped the circuit with Q2 replaced by BSP135 and…
Part Number: UCC28780EVM-021 Other Parts Discussed in Thread: UCC28780 , UCC28070 Hi Team,
We have got UCC28780EVM-021, 45-W, 20-V High-Density Silicon (Si) Based, Active-Clamp Flyback Converter/Evaluation Module. We tested the kit for line and load regulation…
Hello Ulrich,
Thank you for your quick answer. Ok next time I will follow the datasheet method ^^'
Unfortunately, I have done my layout based on the schematic of the eval board (UCC28780EVM-021).
The excel tool give a Rbias1 = 11 k and Rbias2 = 13k…
Hi Ulrich & Jaden
Replace the transformer on UCC28780EVM-021 EVK with Npsa=32:2:6 & Lp=110uH, connect the VDD of the UCC24612 on the secondary side to the 5V output, and R24 &R26=100K, but the 5V output voltage is unstable, could you help to check…
Hi Takahiro-san,
Thanks for reaching out. Please share with your customer UCC28780 which is an active clamp flyback controller. TI has two EVM designs available: UCC28780EVM-002 which uses GaN and UCC28780EVM-021 which uses Si MOSFET.
Best Regards, …
Hello,
Thank you for clarification. I understand that leaving PWMH not connected and using second rectifier controller in PCF topology will be also possible? (the same scheme like for example UCC28780EVM-021 , the only difference PWMH connection).
Best…